I am doing a J2ME application which involves the mathematical manipulation of datatypes integer and double. So the end result would be something like 1.2856 and I would like to round it or truncate, whichever you call it to something along the lines of 1.29. I have tried looking around but realised in J2ME I can't make use of the NumberFormat package to handle this like I do in J2SE. Can anyone provide an alternative solution?

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Have you tried the concrete implementation of NumberFormat, DecimalFormat in java.text, or by you can't make use of NumberFormat, you mean all it's subclasses?

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I can't use java.text, it is not an available package for me to make use of. Is there anything else I could do?

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String number = String.valueOf(2.34566);//turn number to string

String afterDecimalPoint = number.split("(.)")[1];//split the number after the decimal point
//and take the digits after that.
number = afterDecimalPoint;

number = (number.length() > 4 ? number.substring(0,4) : number);//cut it to the number of digits you
//want plus one.

char[] digits = number.toCharArray();//split it into a char array containing a single digit at each index

//this part is an attempt to round up the number.

int lastDigitsValue = new Integer(new String(digits[3])).intValue();//convert last digit to int.


if(lastDigitsValue > 4) { //if it's bigger than four,i.e if it 5 and upwards then

int secondLastDigitsValue = new Integer(new String(digits[2])).intValue(); //get the second last digit

digits[2] = new String((++secondLastDigitsValue)+"").toCharArray()[0]; // increase it by 1;

}

String finalNumber = digits[0]+digits[1]+digits[2]; //Put them back together without the extra digit.

if you want : double numb = Double.parseDouble(finalNumber); //to get it back to being a double

 

 

 

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I didn't think a coding of a method was necessary for a simple arithmetic function such as rounding up to 2 decimal points. But nonetheless, I will try this set of code over the weekend when I have more time to spare. Thanks for the effort though

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